scroll, scrl, wscrl - scroll a curses window
int scroll(WINDOW *win);
int scrl(int n);
int wscrl(WINDOW *win, int n);
The scroll routine scrolls the window up one line. This involves mov-
ing the lines in the window data structure. As an optimization, if the
scrolling region of the window is the entire screen, the physical
screen may be scrolled at the same time.
For positive n, the scrl and wscrl routines scroll the window up n
lines (line i+n becomes i); otherwise scroll the window down n lines.
This involves moving the lines in the window character image structure.
The current cursor position is not changed.
For these functions to work, scrolling must be enabled via scrollok.
These routines return ERR upon failure, and OK (SVr4 only specifies "an
integer value other than ERR") upon successful completion.
Note that scrl and scroll may be macros.
The SVr4 documentation says that the optimization of physically
scrolling immediately if the scroll region is the entire screen "is"
performed, not "may be" performed. This implementation deliberately
does not guarantee that this will occur, to leave open the possibility
of smarter optimization of multiple scroll actions on the next update.
Neither the SVr4 nor the XSI documentation specify whether the current
attribute or current color-pair of blanks generated by the scroll func-
tion is zeroed. Under this implementation it is.
The XSI Curses standard, Issue 4 describes these functions.